1. Field of the Invention
The present invention relates generally to semiconductors, and in particular, to a method, apparatus, and device that provides tunable nanoscale electromechanical coupling in piezoelectric semiconductors.
2. Description of the Related Art
(Note: This application references a number of different publications as indicated throughout the specification by reference numbers enclosed in brackets, e.g., [x]. A list of these different publications ordered according to these reference numbers can be found below in the section entitled “References.” Each of these publications is incorporated by reference herein.)
The nanometer scale domain presents new opportunities for realizing electromechanical transducers with ultralow power consumption, high sensitivity, integrated large scale array architecture, and coupling to mesoscopic phenomena [1]. As an advancement of MEMS, which have become mainstream devices such as optical switches, ink jets, and accelerometers, nanoelectromechanical systems (NEMS) have shown great promise as highly sensitive detectors of mass [2, 3], displacement [4], charge [5], and energy [6]. However, as devices are scaled down, transduction becomes increasingly difficult, hampering efforts to create finely-controlled integrated systems.
In spite of significant progress in the field [7] an efficient, integrated, and customizable technique for actively driving and tuning NEMS resonators remains elusive. Conventional approaches like magnetomotive, electrostatic and electrothermal techniques [7, 8] suffer from either low power efficiency, limited potential for integration, or poor nanoscale control over electromechanical coupling. In contrast, one of the earliest and most straightforward actuation methods, which relies on the piezoelectric effect, provides a means of directly converting electric field into mechanical strain. Discovered by the Curie brothers in 1880 [9], it has since found widespread application in a multitude of systems ranging from clocks, to microwave electromechanical filters, and biosensors. However, new nanoscale functionality enabled by piezoelectric coupling has not yet been systematically explored with top-down NEMS devices.